首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
利用功能标记鉴定普通野生稻中的白叶枯病抗性基因   总被引:1,自引:0,他引:1  
 以9个菲律宾白叶枯病菌小种对供试的9份普通野生稻(Oryza rufipogon Griff.)及1份高感白叶枯病材料IR24进行抗性鉴定,发现IR24对所有的菌株都表现为高感, 6份野生稻材料对9个菌株表现全抗,占参试野生稻总数的67%。取自广西玉林的1份材料只感PXO280(P8),海南万宁的1份材料感PXO71(P4),广州高州的1份材料对PXO79、PXO99和PXO339感病,而这几份材料对其余菌株都表现为抗病,说明每份材料至少含有1个抗性基因。利用已克隆的白叶枯病抗性基因xa5、xa13、Xa21和Xa27的功能标记检测,结果表明9份供试普通野生稻中都不含抗性基因xa5、Xa21;5份为显性Xa13纯合体,4份为隐性抗病xa13杂合体;5份为抗病显性Xa27纯合体,3份为隐性xa27纯合体,1份材料中xa27和Xa27都不存在。  相似文献   

2.
Osa-miR439 is a rice-specific microRNA family. Here we showed that Osa-miR439 acted as anegative regulator in rice immunity against blast fungus Magnaporthe oryzae. Osa-miR439 differentiallyresponded to M. oryzae between susceptible and resistant rice accessions. The accumulation ofOsa-miR439 was constitutively more in the susceptible accession than in the resistant one. Transgeniclines overexpressing Osa-miR439a (OX439a) showed higher susceptibility associating with lower inductionof defense-related genes and less hydrogen peroxide (H2O2) accumulation at the infection sites than thecontrol plants. In contrast, transgenic lines expressing a target mimic of Osa-miR439 (MIM439) displayedcompromised susceptibility associating with increased H2O2 accumulation. Furthermore, we found thatthe expression of three predicted target genes was decreased in OX439a but increased in MIM439 incomparison to control plants, and this expression was differential in susceptible and resistant accessionsupon M. oryzae infection, indicating that Osa-miR439a may regulate rice blast resistance via these genes.Our results unveiled the role of Osa-miR439a in rice blast resistance and provided the potentiality toimprove the blast resistance via miRNA.  相似文献   

3.
Genetic improvement is one of the most effective strategies to prevent rice from blast and bacterial blight(BB) diseases,the two most prevalent diseases jeopardizing rice production.Rice hybrids with dural resistance to blast and BB are needed for sustainable production of food.An incomplete diallele design resulted in 25 crosses between five blast and five BB resistant germplasm accessions.Only one pair of parents,DH146 × TM487,showed polymorphism for all the markers to identify one blast resistance gene Pi25 and three BB resistance genes,Xa21,xa13 and xa5,thus it was used in the marker-assisted selection(MAS).F2 individuals of DH146 × TM487 were genotyped using flanking markers of RM3330 and sequence tagged site(STS) marker SA7 for Pi25.The resistant F2 plants with Pi25 were used for pyramiding BB resistance genes Xa21,xa13 and xa5 identified by the markers pTA248,RM264 and RM153,respectively in subsequent generations.Finally,after selection for agronomic traits and restoration ability among 12 pyramided lines,we acquired an elite restorer line,R8012 including all four target genes(Pi25+Xa21+xa13+xa5).Hybrid Zhong 9A/R8012 derived from the selected line showed stronger resistance to blast and BB,and higher grain yield than the commercial checks uniformally in experimental plots,2007 state-wide yield trial and 2008 nation-wide yield trial.This study provides a paradigmatic example to show that MAS is a practically feasible tool in effectively pyramiding multiple resistance genes.The resultant restoring line and its hybrid would play an important role in securing rice production in China.  相似文献   

4.
Abstract

In pathogen population analysis of 208 Xanthomonas oryzae pv. oryzae(Xoo) strains that were assembled from different parts of India, 21 pathotypes were identified on the basis of disease reactions on near-isogenic lines (NILs) and 13 pathotypes, on rice differentials. Rice cultivars, Jyothi and IR50, which are high yielding but highly prone to bacterial blight (BB) caused by pathogen populations of Xanthomonas oryzae pv. oryzae in India, were chosen. To improve the BB resistance of these two varieties, a pyramid line, NH56, containing four R-genes, Xa4, xa5, xa13, and Xa21, was selected as the R-donor based on resistance to existing pathogen population. The four R-genes were successfully transferred to cultivars through a traditional backcross method and their presence was documented with marker-aided selection (MAS). Thirty BC4F2 plants derived from JxNH56 (cv. Jyothi) and 45 BC4F2 plants derived from IR50xNH56 (cv. IR50) had all four resistance genes (Xa4, xa5, xa13, and Xa21), which should be useful resistance donors for breeding other BB-resistant elite indica varieties.  相似文献   

5.
水稻白叶枯病抗性基因鉴定进展及其利用   总被引:44,自引:7,他引:44  
章琦 《中国水稻科学》2005,19(5):453-459
 1982~1987年,日本热带农业研究中心(TARC)和国际水稻研究所(IRRI)合作采取统一研究方案,创建了国际水稻白叶枯病抗性鉴别系统。统一了命名,删去了重复(包括与Xa3相同的Xa4b、Xa6和xa9)。截至2005年6月,经国际注册确认和期刊报道的水稻白叶枯病抗性基因共30个,其中 Xa22(t)、Xa26(t)、xa26(t)、Xa27(t)、xa28(t)、Xa29(t)和3个Xa25(t)为暂定名基因,有待订正。在30个基因中,21个为显性基因(Xa),9个为隐性基因(xa);13个表现全生育期抗性,15个为成株期抗性,Xa21和Xa25(t) (O. minuta)两个基因在分蘖后期表达抗性。已被定位的抗性基因有17个,即第11染色体上有7个,Xa3、Xa4、Xa10、Xa21、Xa22(t)、Xa23和Xa26;第4染色体上有4个,Xa1、Xa2、Xa12和Xa14;第5染色体上有2个,xa5和xa13;第6染色体上有Xa7和Xa27;第12染色上有Xa25(t);第1染色体上有Xa29(t)。包括Xa1、xa5、Xa21、Xa26五个基因已被克隆。并讨论了合理利用抗性基因等问题。  相似文献   

6.
In marker-assisted breeding for bacterial blight(BB) resistance in rice, three major resistance genes, viz., Xa21, xa13 and xa5, are routinely deployed either singly or in combinations. As efficient and functional markers are yet to be developed for xa13 and xa5, we have developed simple PCR-based functional markers for both the genes. For xa13, we designed a functional PCR-based marker, xa13-prom targeting the In Del polymorphism in the promoter of candidate gene Os8N3 located on chromosome 8 of rice. With respect to xa5, a multiplex-PCR based functional marker system, named xa5 FM, consisting of two sets of primer pairs targeting the 2-bp functional nucleotide polymorphism in the exon II of the gene TFIIA5(candidate for xa5), has been developed. Both xa13-prom and xa5 FM can differentiate the resistant and susceptible alleles for xa13 and xa5, respectively, in a co-dominant fashion. Using these two functional markers along with the already reported functional PCR-based marker for Xa21(p TA248), we designed a single-tube multiplex PCR based assay for simultaneous detection of all the three major resistance genes and demonstrated the utility of the multiplex marker system in a segregating population.  相似文献   

7.
CecropinB与Xa21基因共表达提高转基因水稻白叶枯病抗性   总被引:4,自引:0,他引:4  
为了探明CecropinB与Xa21这两种不同抗病途径的基因单独或共表达后的田间抗白叶枯病表现,利用农杆菌转化技术,获得了这两个基因的单独和共表达后的植株。利用PCR等分子鉴定技术,证明这两个基因已经整合到水稻基因组中。抗病性检测结果表明,Xa21和CecropinB均能提高水稻对白叶枯病的抗性,且Xa21的抗病性较CecropinB明显。Xa21和CecropinB基因共表达后的植株的抗病性比单基因的更强,说明将不同抗性机制的基因共表达,可以在育种上利用以提高水稻的白叶枯病抗性。  相似文献   

8.
利用分子标记辅助育种技术选育高抗白叶枯病恢复系   总被引:13,自引:2,他引:13  
通过常规回交育种结合分子标记辅助选择技术,已将来自IRBB24的2个抗白叶枯病基因, Xa21和Xa4, 聚合到感病的杂交稻恢复系绵恢725中。通过分子标记检测目标基因和亲本遗传背景差异分析快速获得了4个高抗白叶枯病的恢复系姊妹系R207 1、R207 2、R207 3和R207 4。采用与目标抗性基因相应的菲律宾菌系P1、P6 和7个中国病原型代表菌系(CⅠ~CⅦ)对4个姊妹系及其杂交组合进行田间接种。结果表明,这些姊妹系及所配制的杂交组合抗病性强、抗谱广,其中杂交组合G46A/R207 2具有良好的产量潜力,将R207 2定名为蜀恢207。  相似文献   

9.
Rice bacterial blight, one of the major diseases of rice caused by Xanthomonas oryzae pv. oryzae, Xoo, jeopardizes rice diversely. It causes leaf wilting, affects photosynthesis and reduces 1000-grain weight and generally results in yield loss by 20-30 pe…  相似文献   

10.
疣粒野生稻抗白叶枯病新基因的初步鉴定   总被引:1,自引:0,他引:1  
以10个菲律宾白叶枯病菌小种和1个中国白叶枯病菌小种为供试菌系,以高感白叶枯病水稻品种IR24及携有不同抗白叶枯病基因的近等基因系IRBB1等16个材料作为参照,对粳稻品种8411/疣粒野生稻体细胞杂交获得的两个抗白叶枯病新种质SH5和SH76进行了白叶枯病抗谱鉴定。结果表明SH5和SH76在苗期的抗谱较广,并且与已知抗病基因的抗谱不同,但与IRBB5(xa5)和IRBB7(Xa7)相似。分别用xa5和Xa7的分子标记2F_1R和M5进行检测,确定SH5和SH76中不含有xa5和Xa7基因。初步推测SH5、SH76可能含有一个新的抗病基因或者一个连锁的基因簇群。  相似文献   

11.
 以编码HarpinXoo 的hrf1转基因水稻NJH12的cDNA为模板,克隆到了DUF500的保守功能区。序列分析表明,OsDUF500是DUF500家族成员,功能未知。构建OsDUF500的沉默载体,用土壤根癌农杆菌介导的方法转化粳稻 R109,用Hpt抗生素做抗性筛选,获得9个再生株系。经分子鉴定,8个为沉默株系(ABD 2~9)。与野生型相比, ABD株系株高变矮,叶片变短,出现白色空秕谷。白叶枯病抗性鉴定结果表明,OsDUF500沉默株系对水稻白叶枯病的抗性存在差异,病斑长度比野生型明显缩短,病斑面积均在30%以下,株系ABD 3和ABD 5病斑面积分别为12.3%和15.7%,显示出较好的抗性。推测在稻瘟病抗性中上调表达基因OsDUF500对水稻白叶枯病抗性起负调控作用。  相似文献   

12.
水稻抗病基因同源序列的克隆及测序分析   总被引:20,自引:2,他引:20  
 根据已知的NBS LRR类及丝/苏氨酸蛋白激酶类抗病基因结构中氨基酸的保守区域,设计了两组简并引物用于扩增广谱抗稻瘟病品种云系2号中的抗病基因同源序列。结果一共获得11类的NBS-LRR类抗病基因同源片段及16类的丝/苏氨酸蛋白激酶类抗病基因同源片段。所有11类的抗病基因同源系列均含有NBS-LRR类抗病基因的保守序列,如P-loop、Kinase 2、Kinase 3a以及跨膜区域等。所有16类的蛋白激酶的序列均含有丝/苏氨酸蛋白激酶所共有的催化区Ⅵ(共有氨基酸序列:DLKPEN)、Ⅷ(共有氨基酸序列:GT/SXXYXAPE)以及蛋白激酶的其他催化区。两条NBS-LRR类的抗病基因同源片段YR1、YR12分别与抗病基因I2 C-2及Xa1氨基酸同源性很高(>50%)。7条丝/苏氨酸蛋白激酶类的抗病基因同源片段与已克隆的[WTBX][STBX]Xa21、Pto、Lr10[WTBZ][STBZ]等抗病基因的氨基酸序列超过60%的相同以及76%~78%的氨基酸类似。  相似文献   

13.
水稻白叶枯病菌小种分化的监测   总被引:14,自引:4,他引:14  
通过每10年1次对病原菌致病力分化的监测发现,国内稻区病菌小种的组成基本稳定,仅个别小种有所变化。目前流行的优势小种仍为C1和C2群,即携带有[i]Xa3[/i]抗性基因的品种仍可广泛种植;但能够侵染[i]Xa4[/i]抗性基因的C4、C5群小种的数量有所增加,即将达到流行的阈值。为便于与国内外小种鉴别的结果相比较,选用IRRI推出的几个近等基因系材料作为鉴别品种,将中国的白叶枯病菌区分为8个小种(C1~C8)  相似文献   

14.
选用19个不同来源的稻瘟病菌株,对577份国外引进水稻新品种(系)进行不同稻瘟病菌的抗谱分析。研究结果表明,其中有11份品种(系)对19个参测菌株均具有抗性,1份品种(系)对19个参测菌株均为感病;19个参测菌株中,CH187、CH171的致病性最强,而CH362、CH154的致病性最弱;籼稻较粳稻表现出更强的稻瘟病抗性。  相似文献   

15.
携有抗白叶枯病新基因Xa23水稻近等基因系的构建及应用   总被引:20,自引:3,他引:20  
 1993~1998年,构建了携有抗稻白叶枯病新基因Xa23的近等基因系,命名为CBB23。以全生育期高度感病并具有改良株型的籼稻品种JG30为轮回亲本,与携有Xa23的抗性供体H-4杂交,JG30/H-4的F1通过回交、自交直至B5F4,各世代均用与目标基因Xa23相对应的专化小种菌系P6人工接种鉴定,同步进行株型和农艺性状选择,直至抗性稳定和农艺性状类似其轮回亲本。比较了CBB23 (携Xa23) 和IRBB21 (携Xa21) 对20个菌系包括10个菲律宾小种、3个日本小种和7个中国病原型代表菌系的抗谱,Xa23抗所有20 个菌系; Xa21 抗19个菌系,对菲律宾10号小种则高度感病。用近等基因系CBB23构建了JG30/CBB23组合的F2分离群体,通过SSR标记筛选,初步将Xa23定位于水稻第11染色体。进一步筛选出3个与Xa23更紧密连锁的AFLP标记。其中的APKj23与Xa23之间的图距约为1.0 cM。并报道了在抗病育种中已有效的应用了携有Xa23的近等基因系 CBB23。  相似文献   

16.
云南高海拔粳稻区白叶枯病危害日益严重,为了探明该区域白叶枯病菌致病力差异,对白叶枯病进行有效防控。利用15个水稻白叶枯病菌鉴别品种,对采集自海拔1800 m以上稻区11个水稻品种上的32份菌株进行致病力研究。结果发现,致病力最强的菌株是楚雄州的CX28-3和CX30-1,致病率为73.33%;最弱的是大理州剑川县的JC12-2,致病率为0。在高海拔粳稻区,菌株的致病力分化与采集地的海拔高度无关,却与地理距离、采集品种的推广面积有关;而菌株的致病型频率与其采集地的海拔、经纬度、采集品种的推广面积的相关性均不显著。鉴别品种毫糯扬(含新基因)、IRBB14(Xa14)、IRBB4(Xa4)和Tetep(Xa2,Xa16)对所有参试菌株表现为高抗或抗。因此,这些品种内所含的抗性基因值得在云南高原粳稻育种和生产中应用,特别是云南地方稻种毫糯扬,更应加强其新抗病基因的定位和克隆,以为品种选育提供新的抗原。  相似文献   

17.
《Field Crops Research》2005,91(2-3):337-343
Bacterial blight (BB), caused by Xanthomonas oryzae pv. oryzae (Xoo), is one of the most devastating diseases of rice in China. A strongly virulent Xoo strain, designated Z-173, is widely distributed across China and Southeast Asia. Indica rice DV85 is known to carry the two resistance genes, xa5 and Xa7. However, their effectiveness against Z-173 is unknown. Using a recombinant inbred line (RIL) population derived from a cross between DV85 and the susceptible cultivar Kinmaze, we have identified the quantitative trait loci (QTLs) responsible for the resistance of DV85 to Z-173. Following 2 years of phenotyping, three QTLs associated with the resistance were detected. These were linked to RFLP markers X362, X292 and G1091 on chromosomes 3, 5, and 6, respectively. Qxa-5 and Qxa-6 probably correspond to xa5 and Xa7, respectively. Both the xa5 and Xa7 resistances are stable over different years, and act independently of one another in determining resistance. The effect of xa5 was larger than that of Xa7. Efficient ways to improve the resistance to Z-173 are discussed.  相似文献   

18.
Out of 1 989 wild accessions sown in seed boxes for screening, only 1 003 wild accessions with good germination were screened against brown planthopper(BPH), Nilaparvata lugens(St?l) under greenhouse conditions. The collection comprised of accessions from 11 wild species and African cultivated rice. The germplasm was screened for BPH following standard seed box screening technique in the greenhouse. As many as 159 accessions were identified as resistant during the year 2012 based on one year screening. A selected set of BPH resistant accessions were screened again during 2013. Based on the two years screening, seven accessions of O. nivara(AA), one accession of O. officinalis(CC), seven accessions of O. australiensis(EE), five accessions of O. punctata(BB and BBCC) and nine accessions of O. latifolia(CCDD) were confirmed to be resistant to BPH. So far no BPH resistance genes have been identified and designated from O. nivara and O. punctata, hence these may act as new sources of resistance.  相似文献   

19.
20.
云南高原粳稻区白叶枯病菌的致病型初步鉴定   总被引:7,自引:0,他引:7  
利用采自云南高原粳稻区病叶分离的17份水稻白叶枯病菌株,在30份水稻品种上接种进行致病型初步鉴定。研究表明可以将17个菌株分为7个致病型(Ⅰ~Ⅶ),其中Ⅴ型菌为云南高原粳稻区的优势菌群。初步构建了一套包含7个品种(黄玉、毫糯扬、TN1、珍珠矮、IR26、南粳33、金南风)的高原粳稻白叶枯病菌的鉴别品种,明确了7个致病型在这套鉴别品种上的反应型。早生爱国3号(Xa-3)、IR1545-339(xa-5)、IRBB21(Xa-21)、扎昌龙(Xa-22t,Xa-24t)对所接种菌均表现抗病,在云南高原粳稻育种中具有较好的利用前景。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号